Smartphone recycling can serve as a viable side hustle for individuals looking to earn extra income while contributing positively to the environment. As the demand for smartphones continues to grow and new models are released frequently, many people upgrade their devices regularly, leaving older phones behind. This surplus of used or outdated smartphones presents an opportunity for enterprising individuals to engage in recycling and reselling them for profit. To start a side hustle in smartphone recycling, the first step is to establish a reliable source of used smartphones.